onstat -P Partition Buffer Summary

The onstat -P command displays a list showing the partition number and the number of btree, data and
other types of pages in the buffer pool associated with each partition. It also identifies the number of
resident and dirty pages in the buffer pool for each parititon. The output is sorted by partition number.

Percentages

The percentage of pages in the buffer pool that are neither data pages nor index pages.

Flt

Notes

Partitions that contain both index and data pages will have a value in both the Btree and Data columns.
Fragmented (detached) indexes will have a separate partition entry.

The first column of the total line should equal the number of pages in the buffer pool.

Data pages consist of data, remainder and blob pages.

Since V10 and the introduction of user defined page size the individual buffer pools can be seen via onstat -P <page size>

Monitoring and Tuning

The output from onstat -P is useful for identifying how much of a partition (table) is cached and
whether or not its pages have been marked as resident. Heavily hit tables, such as reference tables, are
good candidates for use of the resident capability offered by the CREATE TABLE statement.